53021440 has 72 divisors (see below), whose sum is σ = 132598368. Its totient is φ = 20275200.

The previous prime is 53021431. The next prime is 53021447. The reversal of 53021440 is 4412035.

It is a super-2 number, since 2×53021440² = 5622546199347200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (53021447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28540 + ... + 30340.

It is an arithmetic number, because the mean of its divisors is an integer number (1841644).

Almost surely, 2^53021440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 53021440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66299184).

53021440 is an abundant number, since it is smaller than the sum of its proper divisors (79576928).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

53021440 is a wasteful number, since it uses less digits than its factorization.

53021440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1845 (or 1831 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 53021440 is about 7281.5822456386. The cubic root of 53021440 is about 375.6792193903.

Adding to 53021440 its reverse (4412035), we get a palindrome (57433475).

The spelling of 53021440 in words is "fifty-three million, twenty-one thousand, four hundred forty".